Worktrees tab

[heiskane]

It changes the following:

• Adds a new tab for worktrees
• Can run in bare repositories
• Changing current worktrees
• Lock/Unlock Worktree
• Prune/Force Prune worktree
• Indicate which worktrees are valid/invalid
• Show currently selected worktree

TODO:

• Fix pull/push in worktrees
• Show current branch in each worktree
• Order worktrees?
• Keep track of parent repo? Currently assumes a worktree directory is in bare-repo directory but this might not be the case.
• Use async for fetching worktrees?
• Tests

I followed the checklist:

• I added unittests
• I ran make check without errors
• [ x] I tested the overall application
• I added an appropriate item to the changelog

[stale]

This issue has been automatically marked as stale because it has not had any activity half a year. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.